Dynamic spectrum access technologies based on Cognitive Radio(CR) is under intensive research carried out by the wireless communication society and is expected to solve the problem of spectrum scarcity.However,most enabling technologies related to dynamic spectrum access are con-sidered individually.In this paper,we consider these key technologies jointly and introduce a new implementation scheme for a Dynamic Spectrum Access Network Based on Cognitive Radio(DSAN-BCR).We start with a flexible hardware platform for DSAN-BCR,as well as a flexible protocol structure that dominates the operation of DSAN-BCR.We then focus on the state of the art of key technologies such as spectrum sensing,spectrum resources management,dynamic spectrum access,and routing that are below the network layer in DSAN-BCR,as well as the development of technologies related to higher layers.Last but not the least,we analyze the challenges confronted by these men-tioned technologies in DSAN-BCR,and give the perspectives on the future development of these technologies.The DSAN-BCR introduced is expected to provide a system level guidance to alleviate the problem of spectrum scarcity. Dynamic spectrum access technologies based on Cognitive Radio (CR) is under intensive research carried out by the wireless communication society and is expected to solve the problem of spectrum scarcity. However, most enabling technologies related to dynamic spectrum access are con-sidered individually. this paper, we consider these key technologies jointly and introduce a new implementation scheme for a Dynamic Spectrum Access Network Based on Cognitive Radio (DSAN-BCR) .We start with a flexible hardware platform for DSAN-BCR, as well as a flexible protocol structure that dominates the operation of DSAN-BCR.We then focus on the state of the art of key technologies such as spectrum sensing, spectrum resources management, dynamic spectrum access, and routing that are below the network layer in DSAN-BCR, as well as the development of technologies related to higher layers. Last but not the least, we analyze the challenges confronted by these men-tioned technologies in DSAN-BCR, and give the perspecti ves on the future development of these technologies. DSAN-BCR introduced is expected to provide a system level guidance to alleviate the problem of spectrum scarcity.